- Jan 1 Martinus Beijerinck, Dutch microbiologist & botanist (1st to coin the name virus), dies at 79
- Jan 3 Joseph J C Joffre, French marshal, dies at 78
- Jan 4 Arthemus "Art" Acord, American silent film actor and rodeo champion (Arizona Kid, Hard Fists), commits suicide by poison at 40
- Jan 9 Claude Anet [Jean Schopfer], French writer (La fille perdue), dies at 62
- Jan 9 Wayne Munn, wrestler (b. 1896)
- Jan 10 Oscar Fetrás [Otto Faster], German composer (Mondnacht auf der Alster), dies at 76
- Jan 11 James Milton Carroll, American Baptist pastor, leader, historian, and author (b. 1852)
- Jan 14 William Ernst Johnson, British mathematician, dies
- Jan 21 Felix Blumenfeld, Russian composer, conductor and pianist, dies at 67
- Jan 22 Alma Rubens, American actress (Humoresque), dies of Lobar pneumonia and bronchitis at 33
- Jan 23 Anna Pavlova, Russian prima ballerina and choreographer (Diaghilew, Dying Swan), dies from pneumonia at 49